| name | login-flow-custom-commands |
| description | How to author custom commands for the login-flow CLI using the co-generated SDK. |
Custom Commands for login-flow
Overview
The login-flow CLI supports user-authored custom commands that are
compiled into the binary alongside the auto-generated API commands.
Custom commands get a fully-wired SDK client that inherits the CLI's
auth, retries, TLS, base URL, and global headers — zero configuration required.
Architecture
cli/login-flow/custom.rs ← Your command handlers (protected by .fernignore)
cli/login-flow/sdk.rs ← Generated bridge: client() + block_on()
cli/login-flow/main.rs ← Generated entrypoint (calls custom::register)
login-flow-sdk/ ← Co-generated typed SDK crate
login-flow-types/ ← Co-generated typed model crate
Adding a Custom Command
1. Edit cli/login-flow/custom.rs
This file is protected by .fernignore — fern generate will never
overwrite it. Register commands in the register() function:
use login_flow_sdk::api::*;
pub fn register(app: CliApp) -> CliApp {
let app = app.command(
clap::Command::new("get")
.about("Get a widget")
.arg(clap::Arg::new("widgetId").required(true))
,
|matches, ctx| {
let widget_id = matches.get_one::<String>("widgetId").unwrap();
let client = super::sdk::client(ctx);
let result = super::sdk::block_on(
client.widgets.get(widget_id),
)?;
println!("{}", serde_json::to_string_pretty(&result).unwrap());
Ok(())
},
);
app
}
Then build and test:
cargo build
login-flow get <widgetId>
2. Available SDK Clients
The super::sdk::client(ctx) call returns a login_flow_sdk::api::Client
with the following sub-clients:
| Field | Type | Description |
|---|
client.widgets | login_flow_sdk::api::WidgetsClient | widgets operations |
client.tokens | login_flow_sdk::api::TokensClient | tokens operations |
client.system | login_flow_sdk::api::SystemClient | system operations |
3. Key Patterns
Get the SDK client (execution-sharing, fully authenticated):
let client = super::sdk::client(ctx);
Run an async SDK call from a sync handler:
let result = super::sdk::block_on(
client.some_resource.some_method(args),
)?;
Use typed models for request/response serialization:
use login_flow_sdk::api::*;
4. Authentication
Custom commands automatically inherit the CLI's authentication.
The following auth schemes are configured:
- OAuth2 (oauth-authorization-code): env ``
No manual auth wiring is needed in custom command handlers.
Regeneration Safety
| File | Regenerated? | Notes |
|---|
cli/login-flow/custom.rs | No | Protected by .fernignore |
cli/login-flow/sdk.rs | Yes | Bridges AppContext → SDK client |
cli/login-flow/main.rs | Yes | Calls custom::register(app) |
login-flow-sdk/ | Yes | Co-generated typed SDK crate |
login-flow-types/ | Yes | Co-generated typed models |
After running fern generate, your custom.rs is preserved. All
generated code (SDK, types, glue, main.rs) is updated to match the
latest API spec. If the SDK surface changes (renamed methods, new
sub-clients), update your custom.rs to match.
Build & Test
cargo build
login-flow <your-command> [args]
RUST_LOG=debug login-flow <your-command> [args]